I just got the 2021 PlusPak (I have the 2020 UltraPak+) and the 49Pak (both D/L only).

The installer for the 49Pak only allows installation to the drive where MacOS is installed.

I did that and just merged the BIAB folder (drag and drop when holding ALT, select Merge) with the one on my external drive, but this should not be necessary.

The rest of the 2021 installation seems to have gone without any issues at all.

Your solution is fine, but just for the benefit of others that this might happen to, you can fix it by quitting other running applications on your Mac (command+tab, command+Q), and then running the installer again. It is not clear why that happens on some systems.

I'm not sure when the installer was updated but, as of yesterday, it works properly. I had reported the issue earlier and did the comprehensive testing of the updated installer.

I would download it again and run that.

Mike, this was downloaded and installed today so perhaps it's different for people.

Thanks Andrew. It was only that installer, I had no problems with any of the others.

So?

There was a problem exactly as you described—I found it last week. It was fixed yesterday. I tested the before and after. If Andrew's suggestion does not fix you up, download again and retry.

Sometimes Mac installers have to be run more than once before they "take" properly. This is a well known issue that I had with one of the other updated installers in one of the 20 or so tests that I did last night. Running it a second time did the trick. I only consider it a problem if it fails three times in a row (as did this and another before I reported the issue).

I have owned Macs for 25+ years and I have not seen installers "take" after several tries. I did of course try the installer several times and it did not change. I also tried to install the various parts instead of the entire pak and the issue remained. All the other installers worked fine as reported above.

I posted this mostly to report the issue in case other users have the same issue.

I agree it's a curious issue, and it only happens some of the time, on some Macs. Thanks for posting the problem and your solution... we will look into it further.